We propose to create and operate a research resource for the development of area detector technology for protein crystallography. This technology will be applied to both synchrotron x-ray sources, such as Argonne's Advanced Photon Source, and laboratory x-ray generators. Our present projects to develop integrating area detectors using the charge-coupled device (CCD) will be coordinated and combined, permitting more rapid and more orderly development of this crucial hardware. Advanced detector systems will be developed which incorporate recent technological advances in CCD chips, fast computers, fast disk memories, and fiber optics. These detectors will have high spatial resolution, large dynamic range, large areas, high efficiency, and high readout speeds. The Midwest Area Detector Facility (M.A.D.) will be established at Argonne for conventional x-ray source applications of detectors and incorporated into the Research Resource as a service to the community. Finally, we will develop a center for detector software development, which is desperately needed in this growing field. We will develop computer programs that address three problems: rapid data transfer, rapid processing of the vast quantities of monochromatic diffraction data made available by synchrotron-based detectors, and the collection and processing of Laue diffraction images.